Consumers who purchase a Vista-based computer on or after June 26 will be allowed to upgrade to Windows 7 for free, according to a leaked corporate memo from electronics retailer Best Buy.

Windows 7 screen shot
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The memo states that Best Buy (and presumably its competitors) will launch a "Technology Guarantee" program on June 26, under which anyone who purchases a PC running Vista Home Premium, Business, or Ultimate can install Windows 7 at no extra charge when the latter becomes available Oct. 22.

Best Buy also will launch pre-sales of Windows 7 on June 26, according to the memo -- which was first obtained by tech blog Engadget.

The memo, titled "Best Buy's Plan for the Windows 7 Launch," was recently distributed to Best Buy store managers and technical support personnel. In it, Best Buy execs tout the advantages of Windows 7 over Vista. "This new operating system isn't just a 'Vista that works' program -- it's a new operating system with improved productivity, functionality and creativity that uses less computer resources," the memo states.

"In simpler terms, this means less waiting, fewer clicks and less complexity for end users," it continues. Retailers like Best Buy are counting on Windows 7's pending release to spur an uptick in flagging computer sales.

Speaking at the Computex computing expo in Taipei, Steve Guggenheimer, corporate VP for Microsoft's OEM computing unit, said last week that more details of the upgrade program would be released soon.

Such upgrade programs are generally meant to convince consumers not to hold off purchasing PCs during the time period between when a new product is announced and when it's actually available.

Microsoft needs to tread carefully when it comes to upgrade programs. The company was sued last year by consumers who complained that some Windows XP PCs sold as "Vista Capable" prior to Vista's launch in January 2007 were anything but.

Guggenheimer said Microsoft plans to release the Windows 7 code to manufacturers in the second half of July. Microsoft will ship several versions of Windows 7, including Starter Edition, Home Premium, Professional, Enterprise, and, for emerging markets only, Home Basic.

Microsoft is hoping that the Windows 7 operating system helps it recover from the Vista debacle. Vista failed to catch on with mainstream computer users and businesses have shunned it outright. Windows 7 is said to be considerably lighter and easier to use than its predecessor. It also includes slick new features such as built-in support for touch screens and tools that improve day-to-day tasks such as desktops searches and PC-to-PC file transfers.

The Windows 7 Touch Pack includes Microsoft Surface Globe, a 3-D map of the Earth that users can navigate through with their fingertips; Surface Collage, a digital photo organizer and editing program; and Microsoft Surface Lagoon, an aquatic-themed screen saver in which fish and other marine creatures react to touch-screen inputs.

InformationWeek has published an in-depth report on Windows 7. Download the report here (registration required).